410 Beecher and Clarke — Lower Oriskany 



Art. LII. — Notice of a new Lower Oriskany Fauna in 

 Columbia County, New York ; by C. E. Beecher. With 

 an annotated list of fossils • by J. M. Clarke. 



In 1890, while making collections and geological sections 

 in the Becraft's Mountain region of Columbia Coimt}^ New 

 York, a fauna was discovered by the writer, which in many 

 respects is new to the State. Its affinities are with the Oris- 

 kany, but its geological position is below the true Oriskany 

 sandstone. It appears to include a part, at least, of what has 

 been considered as the Upper Pentamerus limestone, and has 

 been referred to the Lower Helderberg group on account of 

 its lithological characters and upon insufficient paleontological 

 grounds. The fauna of the Upper Pentamerus in its original 

 locality (Schoharie, N. Y.) has previously been recognized to 

 contain several species quite distinct from the Scutella, Shaly, 

 and Lower Pentamerus limestones, which represent the typical 

 Lower Helderberg group. Moreover, as the complete fauna 

 has remained unknown and the series has been confused with 

 the underlying Scutella limestone, no exact correlations have 

 been made. 



From the fossils now known from Becraft's Mountain and 

 several other localities, it is evident that the relations of the 

 fauna contained in the upper beds of the series above the 

 Scutella limestone and just below the Oriskany sandstone are 

 with the latter, and not with the Lower Helderberg group. 

 This is shown by the presence in these beds of such typical 

 Oriskany species as Edriocrinus sacculus, Pholidops termi- 

 nates, Leptostrophia magnifica, Hipjparionyx proximus, 

 Leptocmlia fabeUites, Spirifer arrectus, Spirifer arenosns, 

 Cyrtina rostrata, Rkynchonella oblata, and Rensselceriaovoides. 

 This list has been revised by Mr. C. Schuchert, who has made 

 a careful study of the Oriskany brachiopods. 



At Becraft's Mountain the rock is a hard, cherty, arenaceous 

 limestone, weathering into a rotten fine-grained sandstone, 

 preserving the moulds of the fossils or their silicified replace- 

 ments. On Catskill Creek, near Leeds, as shown by speci- 

 mens received from Mr. W. W. Dodge, the rock contains less 

 sand, and does not weather into a softer condition. At Port 

 Jervis, N. Y., it is in general still more calcareous, although there 

 are some cherty layers, and many of the fossils are silicified. 

 Here, too, the series is continuous from the Oriskany sand- 

 stone down through the trilobite beds of Mather, Horton and 

 Barrett. The arenaceous character of the beds gradually 



